Drawing board or work table with raisable and inclinable working surface



Dec. 19, 1967 P. PARIGI 3,358,520

DRAWING BOARD OR WORK TABLE WITH RAISABLE AND INCLINABLE WORKING SURFACE 5 Sheets-Sheet 1 Filed July 26, 1966 INVENTOR ILl'ill ATTORNEY Dec. '19, 1967 P. PARIGI 3,358,520

DRAWING BOARD OR WORK TABLE WITH RAISABLE AND V INCLINABLE WORKING SURFACE Filed July 26, 1966 3 Sheets-Sheet 2 PAOLO PARIGI ATTORNEY Dec. 19, 1967 P. PARIGI DRAWING BOARD OR WORK TABLE INCLINABLE WORKING WITH RAISABLE A SURFACE 5 Sheets-Sheet 5 Filed July 26, 1966 INVENTOR PAOLO PARIGI BY 4%, M

ATTORNEY United States Patent 3,358,620 DRAWING BOARD OR WORK TABLE WITH RAISABLE AND INCLINABLE WORKING SURFACE Paolo Parigi, Via Giotto Ulivi 24, Borgo San Lorenzo, Florence, Italy Filed July 26, 1966, Ser. No. 568,038 Claims priority, application Italy, Aug. 24, 1965, 19,112/ 65 3 Claims. (Cl. 1086) ABSTRACT OF THE DISCLOSURE A drawing board or work table with a raisable and inclinable working surface, an inclined supporting column attached near the center on the underside of the working surface and a counterweight slidably mounted on the outside of the inclined supporting column to balance the weight of the drawing board and facilitate its substantially vertical movement. The inclined supporting column is composed of an inner member of circular cross section which is slidable in telescope fashion in an outer housing. The supporting column stands on a horizontal base integral therewith. The counterweight is mounted on guide means on the side of the outer housing which is opposite the acute angle formed between the inclined column and the vertical base. The guide means permits rolling up and down movement of the counterweight in directions parallel to theinclined supporting column and opposite to the up and down movement of the drawing board. A cable is attached to the upper end of the counterweight and passes over a pulley at the upper end of the outer housing to the lower end of the inner member of the supporting column where it is secured with its other end. A toothed quadrant is integral with or secured to the underside of the drawing board substantially in its center and serves for the pivotal connection of the drawing board to the upper end of the inclined supporting column. A pawl is fixed to the upper end of the supporting column and can be brought into engagement with the toothed segment for locking the same and thereby the drawing board in the desired inclined position. The pawl is connected by means of relatively shiftable connecting rods to a pedal located at the lower end of the supporting column adjacent the horizontal base and permitting actuation of the pawl. The relatively shiftable connecting rods permit actuation of the pawl independently of the adjusted height of the drawing board. A clutch is provided for locking the drawing board at any desired height and for actuation of this clutch a second pedal is provided at the horizontal base adjacent the first mentioned pedal. The pawl is constantly urged against the quadrant by a spring.

The present invention concerns a drawing board or work table with a working surface which is raisable and inclinable.

The drawing board or work table according to the invention comprises a raisable and inclinable working surface, an inclined supporting column attached near the center of the underside of the working surface and having an inner circular section member slidable in telescope fashion in an outer housing, a horizontal base at the lower end of the supporting column, a counterweight slidably mounted on its side opposite an acute angle formed between the column and the base, guide means for the counterweight on said side of the outer housing of the inclined supporting column to permit rolling movement of the counterweight in directions parallel to the supporting column and opposite to the up and down movement of the working surface, a flexible transmission between the upper end of the counterweight and the lower end of the inner circular section member of the inclined supporting column, a toothed quadrant firmly mounted on the lower side of the working surface and pivotally connected to the upper end of the inner member of the inclined supporting column, a pawl fixed to the upper end of the supporting column and engageable with the toothed segment for locking the same and thereby the working surface in an inclined position, a pedal at the lower end of the supporting column adjacent the horizontal base, and relatively shiftable connecting rods between the pedal and the pawl for actuation of the latter independently of the ad justed height of the working surface.

Other particulars will be described with reference to the accompanying drawings, in which:

FIGURES 1, 2 and 3 show the drawing board in a lowered position, FIG. 1 being a section taken along the line B-B of FIG. 2, and FIGS. 2 and 3 being sections taken along the lines AA and CC of FIG. 1 respectively.

FIGURES 4, 5 and 6 give a schematic representation of the drawing board and show, respectively, an external side view in the lowered position, a vertical axial section with the working surface more or less horizontal, and a vertical axial section in the raised position.

FIGURE 7 is an enlarged view in partial vertical axial section.

FIGURE 8 is an external view of some details, partly in section, still further enlarged.

FIGURE 9 is a plan view in section taken along the line D-D of FIGURE 8.

With reference to the drawings, the drawing board is composed of an inclined working surface 1, joined to a supporting column 2, which is inclined and provided with a base 3, preferably in the form of a Y. The supporting column 2 comprises an inner member of circular cross section slidable in telescope fashion in an upright 5 of an outer housing and is balanced by a counterweight 4 which slides externally in the opposite direction along the upright 5 of thehousing of the column 2, being linked to the said housing by means of a flexible transmission 6 (for example, a rope or a chain or similar means) which slides on a pulley 7 (FIGS. 5 and 6); the said counterweight slides freely resting on suitable guides 3 provided on the upright 5.

The inclination of the working surface 1 is obtained by means of a toothed quadrant 9 which is situated below the said surface and turns about the shaft 11 and engages with a pawl 10 which is situated at the top of a rocking shaft 12. Locking of the rotation of the work surface 1 around the shaft 11 is effected by means of the said pawl which is constantly pressed against the toothing of the quadrant 9 by means of a spring 13.

The rocking shaft 12 is of circular section.

Because the distance of the pawl 10 from the attachment of the pedal 14 situated at the base 3 is continually varying due to the raising of the column 2, so that it is practically impossible to obtain a direct linkage, with the system according to the invention, when the column 2 is raised, the rocking shaft 12 slides in a hole 20 in the crosspiece 15 which is attached to the fixed part or upright 5 by means of the support 16. The crosspiece 15 is kept in contact with the pin 17, in a position perpendicular to the support 16, by means of the spring 18 and is jointed to a tie rod 19 which is adjustable.

When it is desired to lock the pawl 10, the pedal 14- is pressed and this, being linked to the tie rod 19, makes the crosspiece 15 slide downwards to the position a and tilts it. During this operation the edges of the hole 20 in the crosspiece 15 are clamped on the shaft 12 and draw it downwards. This movement can be repeated in any po- 3 sition, whatever the length of the rocking shaft 12 and of the column 2. Because the shaft 12 has a circular sec tion, the system functions equally well with drawing boards which have a circular cross-section.

According to a preferred form of realisation of the invention, the movement of the column 2, which is counterbalanced by the counterweight 4 and guided at 8, is checked and braked by a clutch 21 controlled by a second pedal (not illustrated) near to the first 14 by means of a rod 22.

The counterweight 4 which rests on the guides 8 by means of wheels 23 can be made to slide upwards and downwards with means diiferent to those which have been here described and illustrated.

The base 3 of the upright can also be constructed in a shape that is not that of the letter Y but that of the letter C; so too the inclination of the working surface can be regulated by means of a normal type of clutch in the place of the toothed quadrant, this being activated by a suitable, lever situated under the plane of the working surface, without in these ways going outside the ambit of the invention.

What I claim is:

1. A drawing board or work table comprising a raisable and inclinable working surface,

an inclined supporting column attached near the center of the underside of said Working surface and having an inner circular section member slidable in telescope fashion in an outer housing,

a horizontal base at the lower end of said supporting column,

a counterweight slidably mounted on the outer housing of said inclined supporting column on its side opposite an acute angle formed between said column and. said base,

guide means for said counterweight on said side of the outer housing of said inclined supporting column to permit rolling movement of said counterweight in directions parallel to said supporting column and opposite to the up and down movement of said working surface,

a flexible transmission between the upper end of said counterweight and the lower end of said inner circular section member of said inclined supporting column,

a' toothed quadrant firmly mounted on the lower side of said working surface and pivotally connected to the upper end of said inner member of said inclined supporting column,

a pawl fixed to the upper end of said supporting column and engageable withsaid toothed segment for locking the same and thereby the working surface in an inclined position,

a pedal at the lower end of said supporting column adjacent said horizontal base, and

relatively shiftable connectingrod means between said pedal and said pawl for actuation of the latter independently of the adjusted height of said working surface.

2. A drawing board as claimed in claim 1, wherein a clutch is provided for locking the working surface at any desired height and a second pedal is provided at said horizontal base adjacent said first mentioned pedal for actuation of said clutch.

3. A drawing board as claimed in claim 1, wherein a spring is provided for constantly urging said pawl against said quadrant and said pawl is mounted at the top of a rod passing. through the interior of said spring and the lower end of said rod is pivoted to the upper end of a rocking shaft of circular cross section slidablypassing through a hole in a crosspieceslidably attached to a longitudinal support integral with the outer housing and extending into the interior of said inner circular section member, said crosspiece being jointedto an adjustable tie rod pivoted with its other end to said pedal so as tomake said crosspiece slide down and draw with it said, rocking shaft and said pawl when said pedal is pressed down, elastic means being provided between said crosspiece and said longitudinal support to return said pawl and said pedal to their original positions.

References Cited UNITED STATES PATENTS CASMIR A. NUNBERG, Primary Examiner.

DAVID J. WILLIAMOWSKY, Examiner.

G. O. FINCH, Assistant Examiner. 

1. A DRAWING BOARD OR WORK TABLE COMPRISING A RAISABLE AND INCLINABLE WORKING SURFACE, AN INCLINED SUPPORTING COLUMN ATTACHED NEAR THE CENTER OF THE UNDERSIDE OF SAID WORKING SURFACE AND HAVING AN INNER CIRCULAR SECTION MEMBER SLIDABLE IN TELESCOPE FASHION IN AN OUTER HOUSING, A HORIZONTAL BASE AT THE LOWER END OF SAID SUPPORTING COLUMN, A COUNTERWEIGHT SLIDABLY MOUNTED ON THE OUTER HOUSING OF SAID INCLINED SUPPORTING COLUMN ON ITS SIDE OPPOSITE AN ACUTE ANGLE FORMED BETWEEN SAID COLUMN AND SAID BASE, GUIDE MEANS FOR SAID COUNTERWEIGHT ON SAID SIDE OF THE OUTER HOUSING OF SAID INCLINED SUPPORTING COLUMN TO PERMIT ROLLING MOVEMENT OF SAID COUNTERWEIGHT IN DIRECTIONS PARALLEL TO SAID SUPPORTING COLUMN AND OPPOSITE TO THE UP AND DOWN MOVEMENT OF SAID WORKING SURFACE, A FLEXIBLE TRANSMISSION BETWEEN THE UPPER END OF SAID COUNTERWEIGHT AND THE LOWER END OF SAID INNER CIRCULAR SECTION MEMBER OF SAID INCLINED SUPPORTING COLUMN, A TOOTHED QUADRANT FIRMLY MOUNTED ON THE LOWER SIDE OF SAID WORKING SURFACE AND PIVOTALLY CONNECTED TO 